services/src/main/java/org/onap/ccsdk/apps/filters/ContentTypeFilter.java

   1 package org.onap.ccsdk.apps.filters;
   2
   3 import java.io.IOException;
   4 import java.util.Collections;
   5 import java.util.Enumeration;
   6 import java.util.Iterator;
   7 import java.util.LinkedList;
   8 import java.util.List;
   9
  10 import javax.servlet.Filter;
  11 import javax.servlet.FilterChain;
  12 import javax.servlet.ServletException;
  13 import javax.servlet.ServletRequest;
  14 import javax.servlet.ServletResponse;
  15 import javax.servlet.http.HttpServletRequest;
  16 import javax.servlet.http.HttpServletRequestWrapper;
  17
  18 import org.slf4j.Logger;
  19 import org.slf4j.LoggerFactory;
  20 import org.springframework.core.Ordered;
  21 import org.springframework.core.annotation.Order;
  22 import org.springframework.stereotype.Component;
  23
  24 @Component
  25 @Order(Ordered.HIGHEST_PRECEDENCE)
  26 public class ContentTypeFilter implements Filter {
  27
  28     String DEFAULT_CONTENT_TYPE = "application/json";
  29
  30
  31     @Override
  32     public void doFilter(ServletRequest httpReq, ServletResponse httpResp, FilterChain chain)
  33             throws IOException, ServletException {
  34                 String defaultContentType = System.getProperty("ccsdk.defaults.content-type", DEFAULT_CONTENT_TYPE);
  35                 chain.doFilter(new DefaultContentTypeHttpRequest((HttpServletRequest) httpReq, defaultContentType), httpResp);
  36
  37     }
  38
  39     private class DefaultContentTypeHttpRequest extends HttpServletRequestWrapper {
  40         HttpServletRequest httpRequest;
  41         String contentType;
  42         List<String> acceptList;
  43
  44         List<String> headerNames;
  45
  46         public DefaultContentTypeHttpRequest(HttpServletRequest httpRequest, String defaultContentType) {
  47             super(httpRequest);
  48
  49             this.httpRequest = httpRequest;
  50             this.contentType = defaultContentType;
  51             this.acceptList = null;
  52
  53             boolean hasContentType = false;
  54             headerNames = new LinkedList<String>();
  55             Enumeration<String> headerNameEnum = httpRequest.getHeaderNames();
  56             while (headerNameEnum.hasMoreElements()) {
  57                 String curHeaderName = headerNameEnum.nextElement();
  58                 if ("Content-Type".equalsIgnoreCase(curHeaderName)) {
  59                     hasContentType = true;
  60                     contentType = super.getContentType();
  61                     if ("application/yang-data+json".equalsIgnoreCase(contentType)) {
  62                         contentType = "application/json";
  63                     } else if ("application/yang-data+xml".equalsIgnoreCase(contentType)) {
  64                         contentType = "application/xml";
  65                     } else if (contentType.startsWith("text/plain") || contentType.startsWith("*/*")) {
  66                         // Use Accept header, if present, to determine content type.
  67                         boolean acceptsXml = false;
  68                         boolean acceptsJson = false;
  69                         for (Enumeration<String> e = getHeaders("Accept") ; e.hasMoreElements() ;) {
  70                             String curAcceptValue = e.nextElement();
  71                             if ("application/json".equalsIgnoreCase(curAcceptValue)) {
  72                                 acceptsJson = true;
  73                             } else if ("application/yang-data+json".equalsIgnoreCase(curAcceptValue)) {
  74                                 acceptsJson = true;
  75                             } else if ("application/xml".equalsIgnoreCase(curAcceptValue)) {
  76                                 acceptsXml = true;
  77                             } else if ("application/yang-data+xml".equalsIgnoreCase(curAcceptValue)) {
  78                                 acceptsXml = true;
  79                             }
  80                         }
  81                         if (acceptsJson) {
  82                             contentType = "application/json";
  83                         } else if (acceptsXml) {
  84                             contentType = "application/xml";
  85                         } else {
  86                             // If Accept does not specify XML or JSON (could be Accept is missing), use default content type
  87                             contentType = defaultContentType;
  88                         }
  89                     }
  90                 } else if ("Accept".equalsIgnoreCase(curHeaderName)) {
  91                     acceptList = new LinkedList<String>();
  92                     for (Enumeration<String> e = getHeaders("Accept") ; e.hasMoreElements() ;) {
  93                         String acceptValue = e.nextElement();
  94                         if ("application/yang-data+json".equalsIgnoreCase(acceptValue)) {
  95                             if (!acceptList.contains("application/json")) {
  96                                 acceptList.add("application/json");
  97                             }
  98                         } else if ("application/yang-data+xml".equalsIgnoreCase(acceptValue)) {
  99                             if (!acceptList.contains("application/xml")) {
 100                                 acceptList.add("application/xml");
 101                             }
 102                         } else {
 103                             if (!acceptList.contains(acceptValue)) {
 104                                 acceptList.add(acceptValue);
 105                             }
 106                         }
 107                     }
 108                 }
 109                 headerNames.add(curHeaderName);
 110             }
 111             if (!hasContentType) {
 112                 headerNames.add("Content-Type");
 113             }
 114
 115         }
 116
 117         @Override
 118         public String getHeader(String name) {
 119             if (name.equalsIgnoreCase("Content-Type")) {
 120                 return getContentType();
 121             } else {
 122                 return super.getHeader(name);
 123             }
 124         }
 125
 126
 127
 128         @Override
 129         public Enumeration<String> getHeaders(String name) {
 130             if ("Accept".equalsIgnoreCase(name) && (acceptList != null)) {
 131                 return Collections.enumeration(acceptList);
 132             } else {
 133                 return super.getHeaders(name);
 134             }
 135         }
 136
 137         @Override
 138         public Enumeration<String> getHeaderNames() {
 139             return(Collections.enumeration(headerNames));
 140         }
 141
 142         @Override
 143         public String getContentType() {
 144            return contentType;
 145         }
 146
 147     }
 148
 149
 150 }